Code planning for wireless communications

ABSTRACT

Scrambling code conflicts can be mitigated by primary scrambling code reuse that minimizing a potential interference Primary scrambling codes are applied to a first set of cells located in a portion of the network being considered. A second set of cells are evaluated for primary scrambling code reuse based on a distance parameter and/or a coverage area. If the distance parameter is greater than a defined distance, primary scrambling code reuse can be applied. If all distance parameters evaluated are less than the distance parameter, a length of the distance parameter is reduced and the distance between cells is reevaluated.

TECHNICAL FIELD

The subject disclosure relates to wireless communications and, moreparticularly, to code planning for wireless communications.

BACKGROUND

Wide adoption of mobile devices along with ubiquitous cellular datacoverage has resulted in an explosive growth of mobile applications thatexpect always-accessible wireless networking. This explosion has placedstrains on resources that are scarce in the mobile world. On the userside, dropped calls have been blamed for user dissatisfaction. On thenetwork side, instances of dropped calls or poor quality communicationscan occur due to scrambling code confusion, which can occur when amobile device encounters two sectors that utilize the same scramblingcode.

SUMMARY

A simplified summary is provided herein to help enable a basic orgeneral understanding of various aspects of example, non-limitingembodiments that follow in the more detailed description and theaccompanying drawings. This summary is not intended, however, as anextensive or exhaustive overview. Instead, the sole purpose of thissummary is to present some concepts related to some example,non-limiting embodiments in a simplified form as a prelude to the moredetailed description of the various embodiments that follow. It is alsonoted that the detailed description may include additional oralternative embodiments beyond those described in this summary.

The disclosed aspects can be configured to assign scrambling codes tocells while verifying that the scrambling codes are not reused within adefined distance or based on other parameters (e.g., actual coveragearea of each cell). This assignment of scrambling codes can improve(e.g., maximize) the reuse distance of scrambling codes to minimize apotential interference level. The assignment of scrambling codes asdisclosed herein can also mitigate primary scrambling code confusionand/or neighbor conflicts. Further, the disclosed aspects can assignscrambling codes such that radio link failures are mitigated and droppedcall performance is improved (e.g., the occurrence of dropped calls isreduced).

These and other aspects or embodiments are described in more detailbelow.

BRIEF DESCRIPTION OF THE DRAWINGS

Various non-limiting embodiments are further described with reference tothe accompanying drawings in which:

FIG. 1 illustrates an example, non-limiting wireless communicationsenvironment in which the disclosed aspects can be utilized, according toan embodiment;

FIG. 2 illustrates an example, non-limiting system configured toallocate primary scrambling codes to cells, according to an aspect;

FIG. 3 illustrates scrambling code assignments represented as a graphcoloring theory, according to an aspect;

FIG. 4 illustrates another example, non-limiting system for scramblingcode planning, according to an aspect;

FIG. 5 illustrates an example, non-limiting system for consideringdistance and coverage range for scrambling code planning, according toan aspect;

FIG. 6 illustrates a first case where an overlap factor is equal to 1,according to an aspect;

FIG. 7 illustrates a second case having an overlap factor equal to 1.25,according to an aspect;

FIG. 8 illustrates a third case, which has as overlap factor equal to1.5, according to an aspect;

FIG. 9 illustrates an example, non-limiting system for consideringneighbor relations during scrambling code planning, according to anaspect;

FIG. 10 illustrates an example wireless communications networkcomprising two cells, according to an aspect;

FIG. 11 illustrates, a potential scrambling code conflict issue within awireless communications network, according to an aspect;

FIG. 12 is another example wireless communications network illustratinganother scrambling code conflict issue, according to an aspect;

FIG. 13 illustrates an example, non-limiting system for scrambling codeallocation while accounting for various constraints, according to anaspect;

FIG. 14 illustrates an example, non-limiting system that employs anartificial intelligence component, which facilitates automating one ormore features in accordance with the disclosed aspects;

FIG. 15 illustrates an example, non-limiting method for primaryscrambling code reuse planning, according to an aspect;

FIG. 16 illustrates an example, non-limiting method for maximizingprimary scrambling code reuse distance, according to an aspect;

FIG. 17 illustrates an example, non-limiting method for adjusting adistance parameter during primary scrambling code reuse planning,according to an aspect;

FIG. 18 illustrates a method for assigning primary scrambling codes,according to an aspect;

FIG. 19 illustrates a schematic example wireless environment that canoperate in accordance with aspects described herein;

FIG. 20 illustrates a block diagram of access equipment and/or softwarerelated to access of a network, in accordance with an embodiment; and

FIG. 21 illustrates a block diagram of a computing system, in accordancewith an embodiment.

DETAILED DESCRIPTION

Aspects of the subject disclosure will now be described more fullyhereinafter with reference to the accompanying drawings in which exampleembodiments are shown. In the following description, for purposes ofexplanation, numerous specific details are set forth in order to providea thorough understanding of the various embodiments. However, thesubject disclosure may be embodied in many different forms and shouldnot be construed as limited to the example embodiments set forth herein.

It is noted that although various aspects and embodiments are discussedherein with respect to Universal Mobile Telecommunications System(UMTS), the subject disclosure is not limited to a UMTS implementation.For example, aspects or features of the disclosed aspects can beexploited in substantially any wireless communication technology. Suchwireless communication technologies can include Universal MobileTelecommunications System (UMTS), Code Division Multiple Access (CDMA),Wi-Fi, Worldwide Interoperability for Microwave Access (WiMAX), GeneralPacket Radio Service (GPRS), Enhanced GPRS, Third Generation PartnershipProject (3GPP) Long Term Evolution (LTE), Third Generation PartnershipProject 2 (3GPP2) Ultra Mobile Broadband (UMB), High Speed Packet Access(HSPA), Evolved High Speed Packet Access (HSPA+), High-Speed DownlinkPacket Access (HSDPA), High-Speed Uplink Packet Access (HSUPA), Zigbee,or another IEEE 802.XX technology. Additionally, substantially allaspects disclosed herein can be exploited in legacy telecommunicationtechnologies.

In an example embodiment, an aspect relates to a system comprising atleast one memory and at least one processor communicatively coupled tothe at least one memory. The at least one memory storescomputer-executable instructions. The at least one processor facilitatesexecution of the computer-executable instructions to identify a segmentof a wireless communications network for assignment of scrambling codesto a plurality of base stations located within the segment. The at leastone processor also facilitates execution of the computer-executableinstructions to determine a core of the segment. The core is a portionof the segment comprising at least a pre-defined number of basestations. Further, the at least one processor also facilitates executionof the computer-executable instructions to reserve a first set ofscrambling codes of the scrambling codes. The first set of scramblingcodes can be reserved for a first set of base stations of the pluralityof base stations within the core. The at least one processor alsodefines a center for the segment. Further, the at least one processorcan also facilitate execution of the computer-executable instructions toassign a second set of base stations of the plurality of base stationsin the segment. The assignment can be performed in an order based ondistances of the second set of base stations from the center. Further, afirst base station in the first set of base stations and a second basestation of the second set of base stations can be assigned a samescrambling code. Further, the at least one processor facilitatesexecution of the computer-executable instructions to convey respectivescrambling codes to the first set of base stations and the second set ofbase stations.

Another aspect relates to a method that includes determining, by asystem comprising a processor, a first allocation of a first set ofprimary scrambling codes to a first set of base station of a pluralityof base stations located in a populated area of a wirelesscommunications network having at least a pre-defined population. Themethod also includes determining, by the system, a second allocation ofa second set of primary scrambling codes for each base station of asecond set of base stations of the plurality of base stations. Thedetermining is based on at least one of a distance between base stationsof the plurality of base stations and a coverage area of each basestation. Further, the method includes assigning, by the system, thefirst set of primary scrambling codes to the first set of base stationsand the second set of primary scrambling codes to the second set of basestations. Scrambling codes of the first set of primary scrambling codesare reused in the second set of primary scrambling codes.

A further aspect relates to a non-transitory computer-readable storagemedium storing computer-executable instructions that, in response toexecution, cause a system including a processor to perform operations.The operations include identifying a portion of a network that comprisesat least a pre-defined number of base stations and assigning primaryscrambling codes to a first set of base stations in the portion of thenetwork. The operations can also include evaluating a second set of basestations in the portion of the network for reuse of the primaryscrambling codes. The evaluation can be based on a distance between basestations that are assigned a same scrambling code and a coverage area ofeach base station. Further, the operations include selectively applyingthe primary scrambling codes to the second set of base stations as aresult of the evaluating. A same primary scrambling code is applied to afirst base station in the first set of base stations and a second basestation in the second set of base stations.

Referring initially to FIG. 1, illustrated is an example, non-limitingwireless communications environment 100 in which the disclosed aspectscan be utilized, according to an embodiment. A wireless communicationsenvironment 100 can comprise any number of cells (e.g., sites, sectors,base stations, and so forth). The illustrated wireless communicationsenvironment 100 includes a first cell 102, a second cell 104, a thirdcell 106, and a fourth cell 108, although more (or fewer) than four cellcan be utilized in a wireless communications environment. Each cell hasa respective geographic area or coverage area. For example, first cell102 has a first coverage area 110, second cell 104 has a second coveragearea 112, third cell 106 has a third coverage area 114, and fourth cell108 has a fourth coverage area 116.

In an example, the cells can be UTRAN (Universal Terrestrial RadioAccess Network) cells. Each cell can be assigned a primary scramblingcode (PSC). A PSC is a code utilized to distinguish each cells'stransmissions from transmissions from other cells. There can be about512 available PSCs, numbered 0 through 511. Although each cell should beassigned a unique PSC, since there are a finite number of PSCs and therecan be thousands of cells, some reuse of each PSC might be necessary ina wireless communications environment.

Also illustrated in FIG. 1 are two mobile devices, labeled as a firstmobile device 118 and a second mobile device 120, although more than twomobile devices can be operated within the wireless communicationsenvironment 100. As utilized herein, a mobile device can include aUMTS-based electronic device, such as, but not limited to, a cell phone,a PDA (personal digital assistant), a media player, a digital camera, amedia recorder, a laptop, a personal computer, a printer, a scanner, atablet, a GPS (global positioning system) module, a gaming module, andso forth. Further, the device can also include UMTS-based appliancesthat can be employed, for example, in a home, office, building, retailstore, restaurant, hotel, factory, warehouse, and so on. As previouslynoted, although the various aspects are discussed herein with referenceto UMTS, the aspects are not limited to an UMTS implementation. Instead,the various aspects can be utilized with other network technologies andUMTS technology is utilized herein for purposes of simplicity.

The mobile devices differentiate each of the cells based on the PSC ofthe cell. Thus, the mobile devices should know the correct PSC of a cellin order to access that cell (e.g., during handoff). For example, PSCscan differentiate WCDMA (Wideband CDMA) radios from one another, asdetected by mobile devices (e.g., user equipment). If the mobile devicecould receive, at the same time, communication from more than one cell(e.g., a first cell and a second cell) assigned the same PSC, confusion(or conflict) can result. In this case, the mobile device might intendto handoff to a specific cell, but is instead handed off to a differentcell due to the PSC conflict.

As discussed above, Radio Access Network (RAN) planners have about 512possible PSCs to assign to each of the radios (e.g., cells). Thus, therecan be PSC reuse throughout the various wireless communications networkssince a network can have more than about 512 cells. The RAN planners canconsider the radios that are located in proximity to each other andattempt to distribute the PSCs so that two or more cells having the samePSC are not able to be detected by a mobile device at the same time(e.g., two cells using the same “scrambling code” interfere with eachother).

For convenience, RAN planners might assign the same PSC to all carriersin the same sector. In an example, a base station might have threesectors and, within each sector, there might be four carriers. Amongthese four carriers, the same PSC might be assigned (e.g., carrier 1 isassigned PSC 200 and, within the same sector, carrier 2 is assigned PSC200) since there is usually no interference or ambiguity betweendifferent carriers. The ambiguity (and thus conflict) exists when PSCsare assigned to cells in the same carrier frequency. As stated, thenoted scheduling is a convenience for RAN planners, however, thisdeployment of PSC reuse might not maximize the reuse distance. This isbecause a given carrier might only be deployed in a selected area anddoes not allow for the reuse distance to be extended as far as possible.

The various aspects disclosed herein can provide a direct means toallocate PSCs to each of the cells (e.g., UTRAN cells) while maximizingPSC reuse distance and/or while minimizing the potential interferencelevel. By maximizing the reuse distance (or by minimizing the potentialinterference level), potential problems can be mitigated, includingproblems associated with PSC confusion or PSC conflict. The disclosedaspects can also perform PSC planning with considerations for both thedistance between the cells and/or azimuth and/or beam width (e.g.,coverage area) considerations.

FIG. 2 illustrates an example, non-limiting system 200 configured toallocate primary scrambling codes to cells, according to an aspect. Theallocation of PSCs is performed while minimizing the potentialinterference level, which can mitigate the occurrence of PSC conflicts.Other benefits of minimizing the potential interference level with thedisclosed aspects can include improved network performance and areduction in the number of dropped calls. Another benefit can beincreased busy hour Erlang load capacities, where Erlang is astatistical measure of offered load or carried load on networkresources. Other benefits can include improvements in call setup ratesand improved handoffs.

In an example, each UTRAN cell can be assigned a unique PSC. UTRAN cellsare differentiated by their PSCs and mobile devices should know thecorrect PSC of a cell in order to access that cell. Further, PSC reusedistance can be maximized to avoid potential problems. Such problemsthat can occur include PSC “confusion”, which occurs when the networkcannot identify which cell the mobile device is reporting on. Anotherproblem that can occur is interference among cells sharing the same PSC.Poor PSC planning can result in dropped calls.

PSCs are assigned by RF engineers based on high level engineering rules.This can be performed based on principles to minimize PSC collisions,however, PSCs are assigned on an ad-hoc basis through a manual method.As UTRAN expands coverage, PSC assignment to new cells should take intoaccount other existing cells. Due to the large effort involved, thismight be performed by considering immediate neighbor cells only,resulting in a non-optimal PSC plan. To simplify the PSC assignmentproblem, the same PSC can sometimes be used for all carriers for thesame face. Though this provides some degree of simplicity for RFengineers, it can cause sub-optimal PSC assignments. The net results aremore dropped calls, more call setup failures, and reduced Erlandcapacity to the network.

The disclosed aspects provide a PSC tool that can improve the reusedistance, eliminate PSC/neighbor conflicts, reduce radio link failures,and improve the dropped call performance. Further, the disclosed aspectscan be utilized to assign scrambling codes to carriers. This can befacilitated by ensuring that PSCs are not reused within an “optimal”distance.

System 200 can be implemented in a network (e.g., base station, accesspoint, sector, NodeB, site, and so forth). As previously noted, althoughthe various aspects are discussed herein with reference to UMTS, thedisclosed aspects are not limited to an UMTS implementation. Instead,the various aspects can be utilized with other network technologies andUMTS technology is utilized herein for purposes of simplicity whileexplaining the various aspects.

System 200 can include at least one memory 202 that can store computerexecutable components and computer executable instructions. System 200can also include at least one processor 204, communicatively coupled tothe at least one memory 202. The at least one processor 204 canfacilitate execution of the computer executable components andinstructions stored in the memory 202. It is noted that although one ormore computer executable components may be described herein andillustrated as components separate from memory 202 (e.g., operativelyconnected to memory and operatively connected to each other), inaccordance with various embodiments, the one or more computer executablecomponents could be stored in the memory 202. Further, while variouscomponents have been illustrated as separate components, it will beappreciated that multiple components can be implemented as a singlecomponent, or a single component can be implemented as multiplecomponents, without departing from example embodiments.

System 200 can also include a cluster component 206 that can beconfigured to identify a segment of a wireless communications networkfor assignment of PSCs to a plurality of cells located within thesegment. For example, the wireless communications environment caninclude thousands of cells, only four of which are illustrated. Due tothe vast number of cells and the finite number of available PSCs (e.g.,about 512 PSCs) there might be a need to assign and/or reassign PSCswithin the network. Such a need might arise in the case where additionalcells or base stations are deployed (e.g., to provide additional networkresources for use within the geographic area). In anotherimplementation, the need to reassign PSCs might arise due to thedetection of PSC conflicts and/or the presumption of PSC conflicts dueto problems within the network (e.g., dropped calls, poor call quality,and so forth).

As indicated, a wireless communications network can include thousands ofcells. However, it might not be feasible to assign and/or reassign PSCsto all of the thousands of cells at substantially the same time sincethe cells are taken offline (e.g., turned off) during at least a portionof the assignment/reassignment process. Thus, cluster component 206 canidentify one or more segments for assignment/reassignment of the PSC forcells within the segment. The identified segment can comprise a set ofcells, which can be taken offline for the PSC assignment/reassignmentprocess.

In an example, the cluster component 206 can identify the segment basedon the different markets and/or based on different teams (e.g., networkoperators) that are managing the different cells. For example, one teammight be working on cells in the Los Angeles market and another teammight be working on cells within the San Francisco market or the SanDiego market. When the Los Angeles team is ready to perform PSCplanning, the team cannot assume that cells within the San Diego or SanFrancisco market can be changed. Thus, the territory can be defined(e.g., by cluster component 206) and boundaries around that territorycan be established. At least a subset of cells within the boundaries canbe modified during the PSC assignment/reassignment. Thus, the subset ofcells within the boundaries are considered during the PSC planning andcells outside the boundaries can be ignored.

In another implementation, the PSCs associated with cells locatedoutside boundary of the segment of the wireless communication networkcan be locked and PSC planning is not performed on those cells. Lockingthe cells close to the region's boundary can isolate the impact of PSCplanning to other regions. Further, when PSC planning is performed onthe cells within the segment, whose PSCs are not locked, reuse distancesof the locked cells (e.g., cells located outside the boundaries) are notconsidered. In an implementation, to lock the cells a restriction isapplied to the PSCs of the cells outside the boundary.

Also included in system 200 is a density component 208 that can beconfigured to determine a portion of wireless communications networksegment that comprises at least a pre-defined number of cells. Forexample, the pre-defined number of cells can be a portion that comprisesthe most cells. The portion of the network is referred to as the core ofthe segment. The portion of the segment (e.g., core) having at least thepre-defined number of cells can be identified first because this can bea difficult portion of the segment in which to assign PSCs. A distributecomponent 210 can be configured to reserve a first set of PSCs for afirst set of cells within the core. Thus, even though the core mighthave more than about 500 cells, at least about 500 cells can be assigneddifferent PSCs before the need arises to reuse PSCs within that segment.

An apportion component 212 can be configured to assign a second set ofPSCs to a second set of cells in the segment. The apportion component212 can assign the second set of PSCs on a cell by cell basis. Further,the assignment of the second set of PSCs can be in an order based ondistances of the second set of cells from a center defined for thesegment. In an implementation, the center of the segment can be thecenter of the core. However, the disclosed aspects are not so limitedand the center of the segment can be located elsewhere within thesegment, including within the core. The apportion component 212 can alsobe configured to assign a third (or more) set of PSCs to a third (ormore) set of cells in the segment.

The second set of PSCs (and subsequent sets of PSCs) repeat or reuse thesame PSCs as the first set of PSCs (e.g., PSC reuse), since there is afinite number of PSCs that can be used. Therefore, in an implementation,the same PSC used within the first set of PSCs and the second set ofPSCs are assigned, by the apportion component 212, to a first cell inthe first set of cells and to a second cell in the second set of cellsin a manner that increases a distance between cells that are assigned asame PSC.

In an implementation, the assignment of the second set of PSCs (andsubsequent sets of PSCs) can be based on a distance parameter associatedwith a current cell being evaluated (e.g., the cells are evaluated on acell by cell (or individual) basis). In another implementation, if morethan one cell from the second set of cells meets the distance parameter,a local random search can be conducted. For example, there is backtracking and a local search performed to determine if a differentassignment can be made that increases the distance between cells thatare assigned the same PSC or that minimizes a potential interferencelevel.

In a further implementation, if at least one cell fails to satisfy thecondition with respect to the distance parameter, a length of thedistance parameter can be decreased. In still another implementation,the assignment of the PSCs can include finding at least one PSC based ona distance parameter and a coverage range for the first cell (of thefirst set of cells) and a second cell (of the second set of cells).

In some implementations, a neighbor violation can be removed if neighborcells share a common PSC. Thus, if a first cell and a second cell areidentified as neighbors (e.g., in a neighbor list), both the first celland the second cell might not be permitted to share the same PSC. Inanother implementation, any two cells in a common neighbor list shouldnot be assigned the same PSC. In a further implementation, any two cellsin a combined neighbor list of an active set should not be assigned tothe same PSC.

In some implementations, cells on a same NodeB can be assigned PSCs suchthat there is a PSC separation that conforms to a pre-defined separationamount. For example, the pre-defined separation amount can be a minimumnumber of PSCs that should be located between assigned PSCs. In anexample, PSC separation for cells on a same NodeB might be eight. Forpurposes of this example, a NodeB is treated as a physical tower,however according to various implementations, a tower can have multipleNodeBs. Thus, further to this example, if a first cell on the NodeB isassigned PSC 211, then a second cell (or other cells), on the sameNodeB, cannot be assigned PSCs 212, 213, 214, 215, 216, 217, or 218, ormore (or PSCs 204, 205, 206, 207, 208, 209 or 210, or less). Thepre-defined PSC separation amount can be assigned in order to minimizeinterference.

An output component 214 can be configured to convey respective PSCs tothe first set of cells and the second set of cells (as well as tosubsequent sets of cells). For example, after the PSC planning iscompleted, the output component 214 can cause each cell to be updatedwith its new PSC. The PSC planning and subsequent assignments can beperformed automatically such that dynamic deployment of PSCs can occuron an as need basis or based on other criteria (e.g., potential PSCconflicts have been detected, new cells have been deployed in thenetwork and so forth).

In accordance with some aspects, various information related to PSCassignment can be stored in one or more data store(s) 216 or in anothercomputer readable storage medium. It is noted that a data store caninclude volatile memory or nonvolatile memory, or can include bothvolatile memory and nonvolatile memory. By way of illustration, and notlimitation, nonvolatile memory can include read only memory (ROM),programmable ROM (PROM), electrically programmable ROM (EPROM),electrically erasable PROM (EEPROM), or flash memory. Volatile memorycan include random access memory (RAM), which can operate as externalcache memory. By way of illustration and not limitation, RAM isavailable in many forms such as static RAM (SRAM), dynamic RAM (DRAM),synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhancedSDRAM (ESDRAM), Synchlink DRAM (SLDRAM), and direct Rambus RAM (DRRAM).The memory (e.g., data stores, databases, and so on) of the variousdisclosed aspects is intended to comprise, without being limited to,these and any other suitable types of memory. In an aspect, datastore(s) 216 is included as a component within the disclosed system(s).However, according to other aspects, the data store(s) 216 can belocated remote from the system(s) but can be accessed by the system(s),such as over an air interface.

FIG. 3 illustrates scrambling code assignments represented as a graphcoloring theory, according to an aspect. Graph coloring is a specialcase of graph labeling and refers to an assignment of labels, referredto as “colors”, to elements of a graph. The assignment of colors can besubject to constraints. In the example edge coloring graph, colors areassigned to each edge so that adjacent edges do not share the samecolor.

In further detail, the PSC conflict issue is related to a coloringproblem. Vertices, illustrated as circles, represent cells. An edge,illustrated as a line, is defined between two vertices if (and only if)cell distance (or weighted cell distance) is less than a distanceparameter, such as a PSC reuse distance. For explanation purposes, thesimple graph utilizes three colors. A first color is represented byfilled circles 302, 304, 306, and 308. A second color is represented bypartially filled circles 310, 312, and 314. A third color is representedby unfilled circles 316, 318, and 320.

For the PSC planning issue, the question is whether the vertices can becolored by 512 colors, such that no two adjacent vertices share the samecolor. The 512 colors represent the number of PSCs that can be assigned.It should be noted that although generally 512 PSCs are available (e.g.,numbered 0 to 511), some PSCs might be reserved and not available forassignment to cells. For example, the available PSCs can be PSCs 0through 503, PSC 510, and PSC 511 (where PSCs 504 through 509 arereserved).

The graph coloring problem is a NP-Complete equation and thus,exponential time is generally needed to solve the equation by linearprogramming. Further, in some aspects a heuristic algorithm can beutilized, such as a greedy coloring algorithm, in an attempt to performPSC planning. For example, greedy coloring can be based on a specificvertices ordering. Further information related to a heuristic approachthat can be utilized with the disclosed aspects will be provided below.

FIG. 4 illustrates another example, non-limiting system 400 forscrambling code planning, according to an aspect. According to anaspect, system 400 can be configured to minimize a potentialinterference level during PSC planning. In an example, the interferencelevel can be measured by determining the number of times a given cellsite is “detected” when a mobile device is measuring for neighbors. Inanother example, the interference level can be measured by determining arelative interference between two cells, which can be performedexternally (e.g., external tools) or internally (e.g., measurements inthe system).

Additionally or alternatively, system can be configured to maximize aPSC reuse distance during PSC planning. Included in system 400 is adistance evaluator component 402 that can be configured to identify atleast one PSC based on a distance parameter for a current cell of secondset of cells (or subsequent sets of cells).

For example, a cluster component 206 can identify a segment of awireless communications network for which PSCs are to be assigned and/orreassigned. A density component 208 can determine a portion of thesegment that comprises at least a pre-defined number of cells. Further,a distribute component 210 can initialize an assigned pool, which caninclude assigning a first set of PSCs to cells within the segment. Thedistribute component 210 can assign, for example, 506 different PSCs to506 cells in the segment (even if there are more than 506 cells in thesegment). As noted, although there can be 512 PSCs available, some ofthe PSCs might be reserved for other uses and not available forassignment to cells.

In an order based on distances of the second set of cells to the centerof the assigned pool, an apportion component 212 can assign a second setof PSCs to the second set of cells in the segment. The second set ofPSCs can be assigned to each cell one by one (e.g., on an individual, orcell by cell basis). Depending on the number of cells for which PSCs areto be assigned/reassigned, apportion component 212 can be configured toassign a third set of PSCs to a third set of cells, and so on.

The distance evaluator component 402 can identify at least one PSC thathas a reuse distance that is greater than a defined reuse distance for acurrent cell being evaluated. For example, the distance evaluatorcomponent 402 can be configured to ascertain a location of a first cellin the first set of cells (e.g., first cell can be assigned PSC 200) andevaluate a distance between the first cell and a current cell in thesecond set of cells, where the current cell is the cell underevaluation. If the distance is not greater than the defined reusedistance, the current cell is not assigned the PSC of the first cell(e.g., PSC 200 in this example). In this case, the distance evaluatorcomponent 402 proceeds to ascertain a location of a second cell in thefirst set of cells (e.g., assigned PSC 201) and compares the distancefrom the second cell to the current cell being evaluated. If thedistance is greater than the defined reuse distance, the current cellmight be assigned PSC 201. However, if the distance is not greater thanthe defined reuse distance, a subsequent cell in the first set of cellsis evaluated, and so on. If there are multiple PSCs found that satisfythe defined reuse distance, a search component 404 can be configured toperform a local random search.

In an implementation, the distance evaluator component 402 can ascertainthe location of each of the cells (in the first set of cells, the secondset of cells, and the subsequent set of cells) based on a known locationof each of the cells. For example, base stations are placed in a certaingeographic area and, generally, are not moved. Thus, the actual locationof the base station can be known (e.g., when the base station isinstalled). These various locations can be populated in a database or byanother means that can be accessed by distance evaluator component 402.If there are multiple PSCs found that satisfy the defined reusedistance, a search component 404 can be configured to perform a localrandom search.

System 400 can also include an adjustment component 406 that can beconfigured to decrease a defined reuse distance if at least one cellcannot be assigned. In this situation, distance evaluator component 402can identify at least one PSC that has a reuse distance that is greaterthan the adjusted (e.g., decreased) defined reuse distance.

In an implementation, PSC assignment can include a mixed integerprogramming model. According to the programming model the objectivefunction can be to maximize Z (Objective Function: Maximize: Z), whichcan be subject to various parameters.

A first parameter (or constraint) can be a X-Y relation:2*Y[i,j,k]≦X[i,k]+X[j,k],∀i,jεCELL,i≠j;∀kεPSC

where X[i, k] is a binary variable; X[i, k]=1 when cell i is assigned toPSC k, otherwise X [i, k]=0. Y[i, j, k] is a binary varaible; Z is acontinuous variable, minimum distance between cells assigned by samecode. CELL is a set of cells; PSC is a set of PSCs (e.g., 506 codes).

A second parameter (or constraint) can be that there is one PSC percell. According to this constraint, a cell i is assigned to only onePSC, which can be represented as:

$\begin{matrix}{{{\sum\limits_{k \in {PSC}}{X\left\lbrack {i,k} \right\rbrack}} = 1},} & {\forall{i \in {CELL}}}\end{matrix}$

A third parameter (or constraint) can be a lower bound constraint, whichcan be represented as:Dist[i,j]*Y[i,j,k]≧Z,∀i,jεCELL and ∀kεPSCwhere Dist[i, j] is the Parameter of the distance between cell i andcell j, pre-calculated.

The first constraint can define the logical relation between variable Xand variable Y. The first constraint (combined with objective function)can imply that:Y[i,j,k]=1 when X[i,k]=1 and x[j,k]=1; otherwise Y[i,j,k]=0

FIG. 5 illustrates an example, non-limiting system 500 for consideringdistance and coverage range for scrambling code planning, according toan aspect. Included in system is an overlap component 502 that can beconfigured to evaluate a coverage range of each cell and incorporate theevaluation in the PSC planning considerations. For example, overlapcomponent 502 can be configured to utilize a cell's azimuth and beamwidth to determine an overlapping coverage area of two or more cellsthat are being considered during PSC planning.

In some cases, distance is not the sole criteria that should be used topush the reuse distance as far as possible (e.g., maximize reusedistance, increase a distance between cells that are assigned a samescrambling code) to minimize a potential interference level. Thus,distance might not be the final criteria used during PSC planning. Forexample, in dense urban settings, user locations (e.g., mobile devicelocations) can vary by various geographic coordinates includinglatitude, longitude, and altitude (e.g., three-dimensions). In manycities (e.g., Manhattan, Los Angeles, San Francisco, Chicago, and soforth), numerous small footprint sites exist to cover smaller areas.Users, through their respective mobile devices, might be more prone tosee many sites both near and far away due to tall buildings, hilltops,and so forth. With the higher penetration of sites in smaller geographicareas, PSC reuse can become difficult to configure. Thus, according toan implementation, both distance and coverage area can be consideredduring the PSC planning.

For example, a base station might have two cells that are close to eachother. If the cells are facing away from each, even if the physicaldistance between the cells is small, there might not be any actualinterference because the beams are covering different areas. On theother hand, there might be two cells that are physically far away fromeach other, however, although the cells are far apart, due to thepropagation model, the cells might actually interfere with each other.

With reference to the color graph problem discussed above, the twodistance and beamforming scenarios can be represented as removing edgesor by adding extra edges to the color graph. For example, an edge can beadded if the cells are far away from each other but, due to the real oractual coverage area, the cells actually do interfere. If the cells arephysically close but do not interfere, an edge can be removed. Thus, anedge can be defined based on an actual coverage of the cells. This canbe more accurate than using distance as the only criteria.

FIGS. 6-8 illustrate schematic representations of three cases where theprimary scrambling code reuse distance depends on coverage or overlapbetween two cells, according to an aspect. Instead of the defined PSCreuse distance being a universal value, a binary indicator U(i,j) can becalculated based on radio frequency (RF) coverage, where U(i,j)=1indicates that cell i and cell j are not interfering with each otherbased on a coverage map, even if assigned the same PSC. Otherwise,U(i,j)=0. In the colored graph representation discussed above, the edgeis defined if (and only if) U(i,j)=0.

Illustrated in each of the three cases of FIGS. 6-8 are two cells, Celli 602 and Cell j 604. FIG. 6 illustrates a first case 600 where anoverlap factor is equal to 1, according to an aspect. In this case, theweighted distance of Cell i 602 and Cell j 604 is the distance betweenthe cells divided by the overlap factor of the cells, which can beexpressed as:weighted_dist(i,j)=dist(i,j)/overlap_factor(i,j)

FIG. 7 illustrates a second case 700 having an overlap factor equal to1.25, according to an aspect. In this case, the distance between thecells replaces the weighted distance. Thus, the distance between thecells equals the distance between the cells divided by the overlapfactor of the cells, which can be expressed as:dist(i,j)=dist(i,j)/overlap_factor(i,j)

FIG. 8 illustrates a third case 800, which has as overlap factor equalto 1.5, according to an aspect. In the second case 700 of FIG. 7 and thethird case 800 of FIG. 8, the overlap factors of 1.25 and 1.5,respectively, are adjustable factors. According to an implementation,the parameters can be obtained by sophisticated path loss andpropagation calculations.

In an example, ATOLL cell coverage can be incorporated. A recommendedPSC reuse distance should not be a universal value. Instead, the PSCreuse distance should depend on cell coverage between two cells. Forexample, a binary indicator U(i,j) can be calculated based on ATOLLpredicted coverage. U(i,j) means that cell i and cell j are notinterfering with each other based on ATOLL, even if the same PSC code isassigned. It is zero otherwise. In the graph representation, the edge isdefined if (and only if) U(i,j) is equal to zero.

FIG. 9 illustrates an example, non-limiting system 900 for consideringneighbor relations during scrambling code planning, according to anaspect. System 900 can include an association component 902 that can beconfigured to evaluate a neighbor relation between two or more cells andremove a neighbor PSC violation based on the evaluation. Removing theneighbor PSC violation can include reconfiguring a primary scramblingcode in response to a determination that at least two cells are definedas neighbors and share a common primary scrambling code.

In an implementation, association component 902 can determine whether afirst cell and a second cell are defined as neighbors. For example, theassociation component 902 can access one or more neighbor lists(intra-frequency and/or inter-frequency) to make the determination. Aneighbor list is a table that associates each sector or cell with itsneighboring sectors and which a mobile device can use to initiate ahandover request. The neighbor list can be stored in a database ormemory, for example.

In an implementation, association component 902 can be configured toreconfigure a PSC assignment if neighbor cells share a common PSC. Inanother implementation, association component 902 can be configured toreconfigure a PSC assignment if two cells share a common PSC and aredefined as neighbors of a third cell.

For example, FIG. 10 illustrates an example wireless communicationsnetwork 1000 comprising two cells, Cell A 1002 and Cell B 1004,according to an aspect. As illustrated, Cell A 1002 and Cell B 1004 arein close proximity and their respective geographic areas overlap, asindicated at 1006. In this scenario, the PSCs for the cells were notassigned properly and both Cell A 1002 and Cell B were assigned PSC C2.Since these cells are neighbors, a mobile device 1008 might be in theoverlapping coverage area 1006 of the cells and can receivecommunications from both cells. In this case, a conflict is createdbecause the mobile device 1008 has been provided the same identifier(e.g., PSC C2) for both cells. Thus, the mobile device 1008 cannotproperly identify which cell it is communicating with and/or might becommunicating with both cells but the communication is not synchronized.Further, the mobile device 1008 might not be aware that the two cellsare in conflict. This scenario can result in dropped calls and/or highblock error rate as well as other communication problems. For example,the network is unable to identify which cell the mobile device isreporting on. Thus, the mobile attempts to decode both of them,resulting in a high Block Error Rate (BLER)

Additionally or alternatively, a neighbor violation can be removed iftwo cells share a common primary PSC and are defined as neighbors of athird cell. For example, FIG. 11 illustrates, a potential scramblingcode conflict issue within a wireless communications network 1100,according to an aspect. As illustrated, Cell A 1002 and Cell B 1004 havebeen assigned the same PSC, C2. In this scenario, Cell A 1002 and Cell B1004 are not neighbors. However, Cell C 1102, which has been assignedPSC C1, is a neighbor of both Cell A 1002 and Cell B 1004. For example,Cell C 1102 can have a neighbor list that identifies both Cell A 1002and Cell B 1004, as well as other cells, as candidates for the mobiledevice to handover to. As illustrated, the mobile device 1008 can belocated in an overlapping coverage area between Cell C 1102 and Cell A1002 and intends to handover to Cell A 1002 and identifies this cellwith PSC C2. Since Cell C 1102 has two neighboring cells identified withPSC C2, mobile device 1008 can handoff to either Cell A 1002 or to CellB 1004. In this case, Cell C 1102 might believe mobile device 1008intends to handover to Cell B 1104 and facilitates such handover, whichcan result in a dropped communication.

The PSC conflict illustrated in FIG. 11 can cause dropped calls by themobile device 1008 and/or other communication issues. For example, thenetwork can become confused as to the “real” neighbor of the mobiledevice on Cell C. Thus, the mobile device could handoff to the wrongneighbor, resulting in dropped calls.

FIG. 12 is another example wireless communications network 1200illustrating another scrambling code conflict issue, according to anaspect. In this case, Cell A 1002 and Cell B 1004 have been assigned PSCC2; Cell C 1102 has been assigned PSC C1; and Cell D 1202 has beenassigned PSC C3. In this case, mobile device 1008 is between Cell C 1102and Cell D 1202 and would like to handoff. Since Cell A 1002 and Cell B1004 are assigned the same PSC, the potential for PSC conflict occursand mobile device 1008 could hand off to the unintended cell.

As illustrated in FIG. 12, the neighbors of the active set have the samePSC. For example, the combined neighbor list for active set (Cell C andCell D) has neighbors (Cell A, Cell B) with common PSCs. This can resultin the inability to distinguish between Cell A, Cell B, which can causea higher probability of dropped calls.

FIG. 13 illustrates an example, non-limiting system 1300 for scramblingcode allocation while accounting for various constraints, according toan aspect. In an implementation, a cluster component 206 can beconfigured to identify a segment of a wireless communications networkfor assignment of PSCs to a plurality of cells located within thesegment. System 1300 can also include a secure component 1302 that canbe configured to apply a restriction to a third set of cells locatedoutside a boundary of the identified segment.

For example, since cells for which PSCs are being assigned and/orreassigned might be taken off line in order for the updates to beperformed, only portions of a wireless communications network might beupdated at a given time. Thus, the PSCs of cells close to a region'sboundary can be restricted from being changed in order to isolate theimpact of assignment/reassignment of PSCs to other regions.

System 1300 also includes a density component 208 that can be configuredto determine a core (e.g., area comprising at least a pre-defined numberof cells) of the segment. A distribute component 210 can be configuredto reserve a first set of PSCs for a first set of cells within the core.An apportion component 212 can be configured to assign, in an orderbased on distances of the second set of cells from a center of thesegment, a second set of PSCs to the second set of cells in the segmenton a cell by cell basis. The center of the segment can be defined beforethe assignment or at substantially the same time as the assignment.

In an implementation, a distance evaluator component 402 can beconfigured to identify at least one PSC based on a distance parameterfor a current cell of a second set of cells. The distance evaluatorcomponent 402 also can be configured to ignore a reuse distance betweenthe cells whose PSCs are restricted from being changes (e.g., locked).Ignoring the reuse distance can include bypassing assignment of one ormore PSCs based on a distance between the third set of cells and thesecond set of cells, for example.

Additionally or alternatively, system 1300 can include a locationcomponent 1304 that can be configured to determine a geographic locationof each cell. Cells that are at the same physical location (e.g., NodeB)can be identified by location component 1304. The cells at the sameNodeB, for example, can have a pre-defined separation amount. Thus, whena PSC is assigned to each of the cells on the same NodeB, each cell canbe assigned a PSC such that each cell has a PSC separation that confirmsto the pre-defined separation amount. In an example, the pre-defined PSCseparation amount is eight, however, according to some aspects, adifferent pre-defined PSC amount can be utilized. Further, when a cellis being added to the assigned pool, co-NodeB cells already in the poolcan be checked to verify that a PSC separation amount is in conformancewith the pre-defined separation amount.

FIG. 14 illustrates an example, non-limiting system 1400 that employs anartificial intelligence (AI) component 1402, which facilitatesautomating one or more features in accordance with the disclosedaspects. A cluster component 1404, a density component 1406, adistribute component 1408, an apportion component 1410, an outputcomponent 1412, a database 1414, as well as other components (notillustrated) can include functionality, as more fully described herein,for example, with regard to the previous figures. The disclosed aspects(e.g., in connection with PSC planning) can employ various AI-basedschemes for carrying out various aspects thereof. For example, a processfor planning PSC assignments based on minimizing a potentialinterference level and/or maximizing PSC reuse can be facilitatedthrough an example automatic classifier system and process.

An example classifier can be a function that maps an input attributevector, x=(x1, x2, x3, x4, xn), to a confidence that the input belongsto a class, that is, f(x)=confidence(class). Such classification canemploy a probabilistic and/or statistical-based analysis (e.g.,factoring into the analysis utilities and costs) to prognose or infer anaction that should be automatically performed. In the case ofcommunication systems, for example, attributes can be information storedin database 1414, and the classes can be categories or areas of interest(e.g., distances between cell pairs, coverage areas of each cell).

A support vector machine (SVM) is an example of a classifier that can beemployed. The SVM can operate by finding a hypersurface in the space ofpossible inputs, which the hypersurface attempts to split the triggeringcriteria from the non-triggering events. Intuitively, this makes theclassification correct for testing data that is near, but not identicalto training data. Other directed and undirected model classificationapproaches include, for example, naïve Bayes, Bayesian networks,decision trees, neural networks, fuzzy logic models, and probabilisticclassification models providing different patterns of independence canbe employed. Classification as used herein also may be inclusive ofstatistical regression that is utilized to develop models of priority.

As will be readily noted, the disclosed aspects can employ classifiersthat are explicitly trained (e.g., through a generic training data) aswell as implicitly trained (e.g., through observing PSC reuse, observingdistances between cells, receiving extrinsic information, retrievingintrinsic information and so on). For example, SVMs can be configuredthrough a learning or training phase within a classifier constructor andfeature selection module. Thus, the classifier(s) can be used toautomatically learn and perform a number of functions, including but notlimited to assigning PSCs to cells such that minimizing a potentialinterference level and/or maximum reuse distance is achieved. Thecriteria can include, but is not limited to, distances between cells,actual coverage area of each cell, consideration of one or moreconstraints, and so on.

In view of the example systems shown and described herein, methods thatmay be implemented in accordance with the one or more of the disclosedaspects, will be better understood with reference to the following flowcharts. While, for purposes of simplicity of explanation, the methodsare shown and described as a series of blocks, it is to be understoodthat the disclosed aspects are not limited by the number or order ofblocks, as some blocks may occur in different orders and/or atsubstantially the same time with other blocks from what is depicted anddescribed herein. Moreover, not all illustrated blocks may be requiredto implement the methods described hereinafter. It is noted that thefunctionality associated with the blocks may be implemented by software,hardware, a combination thereof or any other suitable means (e.g.device, system, process, component, and so forth). Additionally, it isalso noted that the methods disclosed hereinafter and throughout thisspecification are capable of being stored on an article of manufactureto facilitate transporting and transferring such methodologies tovarious devices. Those skilled in the art will understand that a methodcould alternatively be represented as a series of interrelated states orevents, such as in a state diagram. The various methods disclosed hereincan be performed by a system comprising at least one processor.

FIG. 15 illustrates an example, non-limiting method 1500 for primaryscrambling code reuse planning, according to an aspect. Method 1500starts, at 1502, with determining a first allocation of a first set ofPSCs to a first set of cells located in an area of a wirelesscommunications network having at least a pre-defined population. At1504, a second allocation of a second set of PSCs for a second set ofcells is determined. The determination of the second allocation can beperformed individually for each cell in the second set of cells.Further, the determination of the second allocation can be based on atleast one of a distance between cells of the plurality of cells and acoverage area.

The first set of PSCs are assigned to the first set of cells and thesecond set of PSCs are assigned to the second set of cells, at 1506.Each cell in the first set of cells and the second set of cells isassigned a PSC. A first cell in the first set of cells and a second cellin the second set of cells are assigned a same scrambling code (e.g.,scrambling code reuse).

According to an aspect, method can include identifying that the firstcell and the second cell are defined as neighbors that share a PSC.Further to this aspect, the PSC of the first cell or the second cell ischanged based in part on the neighbor definition. According to anotheraspect, method can include identifying that the first cell and thesecond cell are defined as neighbors by a third cell, wherein the firstcell and the second cell are assigned the same PSC. Further to thisaspect, the method can include changing the PSC of the first cell or thesecond cell as a function of the identifying.

FIG. 16 illustrates an example, non-limiting method 1600 for maximizingprimary scrambling code reuse distance, according to an aspect.Maximizing the reuse distance can mitigate two cells from using the samescrambling when they would interfere with each other. At 1602, a firstset of PSCs is allocated to a first set of cells. The first set of cellscan be located in a populated area of a wireless communications network.At 1604, an allocation of a second set of PSCs are determined for asecond set of cells. The determination can be performed individually ona cell by cell basis.

According to an aspect, the determination includes determining, at 1606,the distance between a first cell of the first set of cells and a secondcell of the second set of cells. At 1608, a determination is made thatthe distance is greater than a pre-defined distance. Thus, at 1610, thePSC of the first cell is reserved for reuse by the second cell.

In accordance with some aspects, the determination includes measuring,at 1606, the distance between a first cell of the first set of cells anda second cell of the second set of cells. Based on this measurement, adetermination is made, at 1612, that the distance is less than apredefined distance. Thus, at 1614, a second distance between a thirdcell of the first set of cells and the second cell is evaluated. At1616, it can be concluded that the second distance is greater than thepredefined distance. At 1618, the PSC of the third cell is reserved foruse by the second cell.

Method continues, at 1620, when the first set of PSCs is applied to thefirst set of cells and the second set of PSCs is applied to the secondset of cells. The application of the first and second set of PSCs isconfigured to provide for maximum reuse distance of the PSCs and/or tominimize a potential interference level. In an example, a potentialinterference level can be determined by measuring a relativeinterference between two cells (e.g., via external tools, viameasurements in the communications network, and so forth). In anotherexample, a potential interference level can be determined by measuringthe number of times a given cell site is “detected” by a mobile devicethat is measuring for neighbors.

FIG. 17 illustrates an example, non-limiting method 1700 for adjusting adistance parameter during primary scrambling code reuse planning,according to an aspect. At 1702, a first set of PSCs are allocated to afirst set of cells. The first set of cells can be identified as beinglocated in a portion of a wireless communications network that comprisesat least a pre-defined number of cells. For example, the portion of thenetwork can be the most densely populated cell area of the network,according to an aspect. At 1704, an allocation of a second set of PSCsfor a second set of cells is determined. The second set of cells can belocated at least in part in the portion of the network comprising atleast the pre-defined number of cells.

According to an aspect, the determination includes, measuring, at 1706,a plurality of distances between cells of the first set of cells andcells of the second set of cells. At 1708, it is concluded that at leastone distance of the plurality of distances does not satisfy a conditionwith respect to a predefined distance. Thus, at 1710, a length of thepredefined distance is reduced.

After the predefined distance length is reduced, at 1712, the pluralityof distances between cells of the first set of cells and cells of thesecond set of cells are re-measured. At 1714, it is determined that atleast one distance of the plurality of distances satisfies a conditionwith respect to the predefined distance. At 1716, the first set of PSCsis applied to the first set of cells and the second set of PSCs isapplied to the second set of cells.

FIG. 18 illustrates a method for assigning primary scrambling codes,according to an aspect. Method starts, at 1802, when an assigned pool isinitialized. The available PSCs are assigned to (or reserved for) afirst set of cells, wherein one PSC is assigned to each cell. The firstset of cells can be located in a portion of a network that comprises atleast a pre-defined number of cells.

At 1804, all unassigned cells i are looped over in an order determinedby a distance from the portion of the network that comprises at leastthe pre-defined number of cells and each of the unassigned cells. Forexample, if there exists any p, such that for all j x[j,p]=1,dist(i,j)>=min_dist, then set x[i,p]=1 and add cell i to the assignedpool. Where x(i,p)=1 if PSC p is assigned to cell i, otherwise x(i,p)=0;dist(i,j) is the distance between cell i and cell j; and min_dist is thepre-defined minimum PSC reuse distance.

Method 1800 continues, at 1806, with a determination whether all cellsare assigned. If all cells are assigned (“YES”), method 1800 ends. Ifall cells are not assigned (“NO”), method 1800 continues at 1804. It isto be understood that looping all unassigned cells, at 1804, can berecursive and method 1800 can continue in such a manner until all cellsare assigned.

By way of further description with respect to one or more non-limitingways to perform PSC planning, FIG. 19 is a schematic example wirelessenvironment 1900 that can operate in accordance with aspects describedherein. In particular, example wireless environment 1900 illustrates aset of wireless network macro cells. Three coverage macro cells 1902,1904, and 1906 include the illustrative wireless environment; however,it is noted that wireless cellular network deployments can encompass anynumber of macro cells. Coverage macro cells 1902, 1904, and 1906 areillustrated as hexagons; however, coverage cells can adopt othergeometries generally dictated by a deployment configuration or floorplan, geographic areas to be covered, and so on. Each macro cell 1902,1904, and 1906 is sectorized in a 2π/3 configuration in which each macrocell includes three sectors, demarcated with dashed lines in FIG. 19. Itis noted that other sectorizations are possible, and aspects or featuresof the disclosed subject matter can be exploited regardless of type ofsectorization. Macro cells 1902, 1904, and 1906 are served respectivelythrough base stations or eNodeBs 1908, 1910, and 1912. Any two eNodeBscan be considered an eNodeB site pair (NBSP). It is noted that radiocomponent(s) are functionally coupled through links such as cables(e.g., RF and microwave coaxial lines), ports, switches, connectors, andthe like, to a set of one or more antennas that transmit and receivewireless signals (not illustrated). It is noted that a radio networkcontroller (not shown), which can be a part of mobile networkplatform(s) 1914, and set of base stations (e.g., eNode B 1908, 1910,and 1912) that serve a set of macro cells; electronic circuitry orcomponents associated with the base stations in the set of basestations; a set of respective wireless links (e.g., links 1916, 1918,and 1920) operated in accordance to a radio technology through the basestations, form a macro radio access network (RAN). It is further notedthat, based on network features, the radio controller can be distributedamong the set of base stations or associated radio equipment. In anaspect, for UMTS-based networks, wireless links 1916, 1918, and 1920embody a Uu interface (UMTS Air Interface).

Mobile network platform(s) 1914 facilitates circuit switched (CS)-based(e.g., voice and data) and packet-switched (PS) (e.g., internet protocol(IP), frame relay, or asynchronous transfer mode (ATM)) traffic andsignaling generation, as well as delivery and reception for networkedtelecommunication, in accordance with various radio technologies fordisparate markets. Telecommunication is based at least in part onstandardized protocols for communication determined by a radiotechnology utilized for communication. In addition, telecommunicationcan exploit various frequency bands, or carriers, which include any EMfrequency bands licensed by the service provider network 1922 (e.g.,personal communication services (PCS), advanced wireless services (AWS),general wireless communications service (GWCS), and so forth), and anyunlicensed frequency bands currently available for telecommunication(e.g., the 2.4 GHz industrial, medical and scientific (IMS) band or oneor more of the 5 GHz set of bands). In addition, mobile networkplatform(s) 1914 can control and manage base stations 1908, 1910, and1912 and radio component(s) associated thereof, in disparate macro cells1902, 1904, and 1906 by way of, for example, a wireless networkmanagement component (e.g., radio network controller(s), cellulargateway node(s), etc.) Moreover, wireless network platform(s) canintegrate disparate networks (e.g., femto network(s), Wi-Fi network(s),femto cell network(s), broadband network(s), service network(s),enterprise network(s), and so on). In cellular wireless technologies(e.g., 3rd Generation Partnership Project (3GPP) Universal MobileTelecommunication System (UMTS), Global System for Mobile Communication(GSM)), mobile network platform 1914 can be embodied in the serviceprovider network 1922.

In addition, wireless backhaul link(s) 1924 can include wired linkcomponents such as T1/E1 phone line; a digital subscriber line (DSL)either synchronous or asynchronous; an asymmetric DSL (ADSL); an opticalfiber backbone; a coaxial cable, etc.; and wireless link components suchas line-of-sight (LOS) or non-LOS links which can include terrestrialair-interfaces or deep space links (e.g., satellite communication linksfor navigation). In an aspect, for UMTS-based networks, wirelessbackhaul link(s) 1924 embodies IuB interface.

It is noted that while example wireless environment 1900 is illustratedfor macro cells and macro base stations, aspects, features andadvantages of the disclosed subject matter can be implemented inmicrocells, picocells, femto cells, or the like, wherein base stationsare embodied in home-based equipment related to access to a network.

To provide further context for various aspects of the disclosed subjectmatter, FIG. 20 illustrates a block diagram of an embodiment of accessequipment and/or software 2000 related to access of a network (e.g.,base station, wireless access point, femtocell access point, and soforth) that can enable and/or exploit features or aspects of thedisclosed aspects.

Access equipment and/or software 2000 related to access of a network canreceive and transmit signal(s) from and to wireless devices, wirelessports, wireless routers, etc. through segments 2002 ₁-2002 _(B) (B is apositive integer). Segments 2002 ₁-2002 _(B) can be internal and/orexternal to access equipment and/or software 2000 related to access of anetwork, and can be controlled by a monitor component 2004 and anantenna component 2006. Monitor component 2004 and antenna component2006 can couple to communication platform 2008, which can includeelectronic components and associated circuitry that provide forprocessing and manipulation of received signal(s) and other signal(s) tobe transmitted.

In an aspect, communication platform 2008 includes areceiver/transmitter 2010 that can convert analog signals to digitalsignals upon reception of the analog signals, and can convert digitalsignals to analog signals upon transmission. In addition,receiver/transmitter 2010 can divide a single data stream into multiple,parallel data streams, or perform the reciprocal operation. Coupled toreceiver/transmitter 2010 can be a multiplexer/demultiplexer 2012 thatcan facilitate manipulation of signals in time and frequency space.Multiplexer/demultiplexer 2012 can multiplex information (data/trafficand control/signaling) according to various multiplexing schemes such astime division multiplexing (TDM), frequency division multiplexing (FDM),orthogonal frequency division multiplexing (OFDM), code divisionmultiplexing (CDM), space division multiplexing (SDM). In addition,multiplexer/demultiplexer component 2012 can scramble and spreadinformation (e.g., codes, according to substantially any code known inthe art, such as Hadamard-Walsh codes, Baker codes, Kasami codes,polyphase codes, and so forth).

A modulator/demodulator 2014 is also a part of communication platform2008, and can modulate information according to multiple modulationtechniques, such as frequency modulation, amplitude modulation (e.g.,M-ary quadrature amplitude modulation (QAM), with M a positive integer);phase-shift keying (PSK); and so forth).

Access equipment and/or software 2000 related to access of a networkalso includes a processor 2016 configured to confer, at least in part,functionality to substantially any electronic component in accessequipment and/or software 2000. In particular, processor 2016 canfacilitate configuration of access equipment and/or software 2000through, for example, monitor component 2004, antenna component 2006,and one or more components therein. Additionally, access equipmentand/or software 2000 can include display interface 2018, which candisplay functions that control functionality of access equipment and/orsoftware 2000, or reveal operation conditions thereof. In addition,display interface 2018 can include a screen to convey information to anend user. In an aspect, display interface 2018 can be an LCD (LiquidCrystal Display), a plasma panel, a monolithic thin-film basedelectrochromic display, and so on. Moreover, display interface 2018 caninclude a component (e.g., speaker) that facilitates communication ofaural indicia, which can also be employed in connection with messagesthat convey operational instructions to an end user. Display interface2018 can also facilitate data entry (e.g., through a linked keypad orthrough touch gestures), which can cause access equipment and/orsoftware 2000 to receive external commands (e.g., restart operation).

Broadband network interface 2020 facilitates connection of accessequipment and/or software 2000 to a service provider network (not shown)that can include one or more cellular technologies (e.g., 3GPP UMTS,GSM, and so on.) through backhaul link(s) (not shown), which enableincoming and outgoing data flow. Broadband network interface 2020 can beinternal or external to access equipment and/or software 2000, and canutilize display interface 2018 for end-user interaction and statusinformation delivery.

Processor 2016 can be functionally connected to communication platform2008 and can facilitate operations on data (e.g., symbols, bits, orchips) for multiplexing/demultiplexing, such as effecting direct andinverse fast Fourier transforms, selection of modulation rates,selection of data packet formats, inter-packet times, and so on.Moreover, processor 2016 can be functionally connected, through data,system, or an address bus 2022, to display interface 2018 and broadbandnetwork interface 2020, to confer, at least in part, functionality toeach of such components.

In access equipment and/or software 2000, memory 2024 can retainlocation and/or coverage area (e.g., macro sector, identifier(s)),access list(s) that authorize access to wireless coverage through accessequipment and/or software 2000, sector intelligence that can includeranking of coverage areas in the wireless environment of accessequipment and/or software 2000, radio link quality and strengthassociated therewith, or the like. Memory 2024 also can store datastructures, code instructions and program modules, system or deviceinformation, code sequences for scrambling, spreading and pilottransmission, access point configuration, and so on. Processor 2016 canbe coupled (e.g., through a memory bus), to memory 2024 in order tostore and retrieve information used to operate and/or conferfunctionality to the components, platform, and interface that residewithin access equipment and/or software 2000.

As it employed in the subject specification, the term “processor” canrefer to substantially any computing processing unit or deviceincluding, but not limited to including, single-core processors;single-processors with software multithread execution capability;multi-core processors; multi-core processors with software multithreadexecution capability; multi-core processors with hardware multithreadtechnology; parallel platforms; and parallel platforms with distributedshared memory. Additionally, a processor can refer to an integratedcircuit, an application specific integrated circuit (ASIC), a digitalsignal processor (DSP), a field programmable gate array (FPGA), aprogrammable logic controller (PLC), a complex programmable logic device(CPLD), a discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsand/or processes described herein. Processors can exploit nano-scalearchitectures such as, but not limited to, molecular and quantum-dotbased transistors, switches and gates, in order to optimize space usageor enhance performance of mobile devices. A processor may also beimplemented as a combination of computing processing units.

In the subject specification, terms such as “store,” “data store,” datastorage,” “database,” and substantially any other information storagecomponent relevant to operation and functionality of a component and/orprocess, refer to “memory components,” or entities embodied in a“memory,” or components including the memory. It is noted that thememory components described herein can be either volatile memory ornonvolatile memory, or can include both volatile and nonvolatile memory.

By way of illustration, and not limitation, nonvolatile memory, forexample, can be included in memory 2024, non-volatile memory (seebelow), disk storage (see below), and memory storage (see below).Further, nonvolatile memory can be included in read only memory (ROM),programmable ROM (PROM), electrically programmable ROM (EPROM),electrically erasable ROM (EEPROM), or flash memory. Volatile memory caninclude random access memory (RAM), which acts as external cache memory.By way of illustration and not limitation, RAM is available in manyforms such as synchronous RAM (SRAM), dynamic RAM (DRAM), synchronousDRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM(ESDRAM), Synchlink DRAM (SLDRAM), and direct Rambus RAM (DRRAM).Additionally, the disclosed memory components of systems or methodsherein are intended to include, without being limited to including,these and any other suitable types of memory.

In order to provide a context for the various aspects of the disclosedsubject matter, FIG. 21, and the following discussion, are intended toprovide a brief, general description of a suitable environment in whichthe various aspects of the disclosed subject matter can be implemented.While the subject matter has been described above in the general contextof computer-executable instructions of a computer program that runs on acomputer and/or computers, those skilled in the art will recognize thatthe various aspects also can be implemented in combination with otherprogram modules. Generally, program modules include routines, programs,components, data structures, etc. that perform particular tasks and/orimplement particular abstract data types. For example, in memory (suchas memory 202) there can be software, which can instruct a processor(such as processor 204) to perform various actions. The processor can beconfigured to execute the instructions in order to implement PSCplanning as discussed herein.

Moreover, those skilled in the art will understand that the variousaspects can be practiced with other computer system configurations,including single-processor or multiprocessor computer systems,mini-computing devices, mainframe computers, as well as personalcomputers, base stations hand-held computing devices or user equipment,such as a PDA, phone, watch, and so forth, microprocessor-based orprogrammable consumer or industrial electronics, and the like. Theillustrated aspects can also be practiced in distributed computingenvironments where tasks are performed by remote processing devices thatare linked through a communications network; however, some if not allaspects of the subject disclosure can be practiced on stand-alonecomputers. In a distributed computing environment, program modules canbe located in both local and remote memory storage devices.

With reference to FIG. 21, a block diagram of a computing system 2100operable to execute the disclosed systems and methods is illustrated, inaccordance with an embodiment. Computer 2102 includes a processing unit2104, a system memory 2106, and a system bus 2108. System bus 2108couples system components including, but not limited to, system memory2106 to processing unit 2104. Processing unit 2104 can be any of variousavailable processors. Dual microprocessors and other multiprocessorarchitectures also can be employed as processing unit 2104.

System bus 2108 can be any of several types of bus structure(s)including a memory bus or a memory controller, a peripheral bus or anexternal bus, and/or a local bus using any variety of available busarchitectures including, but not limited to, Industrial StandardArchitecture (ISA), Micro-Channel Architecture (MSA), Extended ISA(EISA), Intelligent Drive Electronics (IDE), VESA Local Bus (VLB),Peripheral Component Interconnect (PCI), Card Bus, Universal Serial Bus(USB), Advanced Graphics Port (AGP), Personal Computer Memory CardInternational Association bus (PCMCIA), Firewire (IEEE 1194), and SmallComputer Systems Interface (SCSI).

System memory 2106 includes volatile memory 2110 and nonvolatile memory2112. A basic input/output system (BIOS), containing routines totransfer information between elements within computer 2102, such asduring start-up, can be stored in nonvolatile memory 2112. By way ofillustration, and not limitation, nonvolatile memory 2112 can includeROM, PROM, EPROM, EEPROM, or flash memory. Volatile memory 2110 caninclude RAM, which acts as external cache memory. By way of illustrationand not limitation, RAM is available in many forms such as SRAM, dynamicRAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), Synchlink DRAM (SLDRAM), Rambus directRAM (RDRAM), direct Rambus dynamic RAM (DRDRAM), and Rambus dynamic RAM(RDRAM).

Computer 2102 also includes removable/non-removable,volatile/non-volatile computer storage media. In an implementation, thenon-transitory computer-readable storage medium can storecomputer-executable instructions that, in response to execution, cause asystem including a processor to perform operations. The operations caninclude identifying a portion of a network that comprises at least apre-defined number of cells and assigning PSCs to a first set of cellsin the portion of the network. The operations can also includeevaluating a second set of cells in the portion of the network for reuseof the PSCs. The evaluating can be based on a minimum reuse distance anda coverage area of each cell. The operations can also includeselectively applying the PSCs to the second set of cells as a result ofthe evaluating. A same PSC is applied to a first cell in the first setof cells and a second cell in the second set of cells.

In an aspect, the operations can include identifying at least one PSCbased on a distance parameter for a current cell in the second set ofcells, wherein the current cell is being evaluated for PSC reuse. Inanother aspect, the operations can include reassigning a PSC of thesecond cell if the second cell and the first cell are neighbors or areidentified as neighbors by a third cell. According to another aspect,the operations can include locking PSC associated with a third set ofcells, wherein the third set of cells are located outside the portion ofthe network.

FIG. 21 illustrates the removable/non-removable, volatile/non-volatilecomputer storage media as, for example, disk storage 2114. Disk storage2114 includes, but is not limited to, devices such as a magnetic diskdrive, floppy disk drive, tape drive, Jaz drive, Zip drive, LS-100drive, flash memory card, or memory stick. In addition, disk storage2114 can include storage media separately or in combination with otherstorage media including, but not limited to, an optical disk drive suchas a compact disk ROM device (CD-ROM), CD recordable drive (CD-R Drive),CD rewritable drive (CD-RW Drive) or a digital versatile disk ROM drive(DVD-ROM). To facilitate connection of the disk storage 2114 to systembus 2108, a removable or non-removable interface is typically used, suchas interface component 2116.

It is to be noted that FIG. 21 describes software that acts as anintermediary between users and computer resources described in suitableoperating environment. Such software includes an operating system 2118.Operating system 2118, which can be stored on disk storage 2114, acts tocontrol and allocate resources of computer system 2102. Systemapplications 2120 can take advantage of the management of resources byoperating system 2118 through program modules 2122 and program data 2124stored either in system memory 2106 or on disk storage 2114. It is to beunderstood that the disclosed subject matter can be implemented withvarious operating systems or combinations of operating systems.

A user can enter commands or information, for example through interfacecomponent 2116, into computer system 2102 through input device(s) 2126.Input devices 2126 include, but are not limited to, a pointing devicesuch as a mouse, trackball, stylus, touch pad, keyboard, microphone,joystick, game pad, satellite dish, scanner, TV tuner card, digitalcamera, digital video camera, web camera, and the like. These and otherinput devices connect to processing unit 2104 through system bus 2108through interface port(s) 2128. Interface port(s) 2128 include, forexample, a serial port, a parallel port, a game port, and a universalserial bus (USB). Output device(s) 2130 use some of the same type ofports as input device(s) 2126.

Thus, for example, a USB port can be used to provide input to computer2102 and to output information from computer 2102 to an output device2130. Output adapter 2132 is provided to illustrate that there are someoutput devices 2130, such as monitors, speakers, and printers, amongother output devices 2130, which use special adapters. Output adapters2132 include, by way of illustration and not limitation, video and soundcards that provide means of connection between output device 2130 andsystem bus 2108. It is also noted that other devices and/or systems ofdevices provide both input and output capabilities such as remotecomputer(s) 2134.

Computer 2102 can operate in a networked environment using logicalconnections to one or more remote computers, such as remote computer(s)2134. Remote computer(s) 2134 can be a personal computer, a server, arouter, a network PC, a workstation, a microprocessor based appliance, apeer device, or other common network node and the like, and typicallyincludes many or all of the elements described relative to computer2102.

For purposes of brevity, only one memory storage device 2136 isillustrated with remote computer(s) 2134. Remote computer(s) 2134 islogically connected to computer 2102 through a network interface 2138and then physically connected through communication connection 2140.Network interface 2138 encompasses wire and/or wireless communicationnetworks such as local-area networks (LAN) and wide-area networks (WAN).LAN technologies include Fiber Distributed Data Interface (FDDI), CopperDistributed Data Interface (CDDI), Ethernet, Token Ring and the like.WAN technologies include, but are not limited to, point-to-point links,circuit switching networks like Integrated Services Digital Networks(ISDN) and variations thereon, packet switching networks, and DigitalSubscriber Lines (DSL).

Communication connection(s) 2140 refer(s) to hardware/software employedto connect network interface 2138 to system bus 2108. Whilecommunication connection 2140 is shown for illustrative clarity insidecomputer 2102, it can also be external to computer 2102. Thehardware/software for connection to network interface 2138 can include,for example, internal and external technologies such as modems,including regular telephone grade modems, cable modems and DSL modems,ISDN adapters, and Ethernet cards.

It is to be noted that aspects, features, or advantages of the aspectsdescribed in the subject specification can be exploited in substantiallyany communication technology. For example, 4G technologies, Wi-Fi,WiMAX, Enhanced GPRS, 3GPP LTE, 3GPP2 UMB, 3GPP UMTS, HSPA, HSDPA,HSUPA, GERAN, UTRAN, LTE Advanced. Additionally, substantially allaspects disclosed herein can be exploited in legacy telecommunicationtechnologies; e.g., GSM. In addition, mobile as well non-mobile networks(e.g., Internet, data service network such as IPTV) can exploit aspector features described herein.

Various aspects or features described herein can be implemented as amethod, apparatus, or article of manufacture using standard programmingand/or engineering techniques. In addition, various aspects disclosed inthe subject specification can also be implemented through programmodules stored in a memory and executed by a processor, or othercombination of hardware and software, or hardware and firmware.

Other combinations of hardware and software or hardware and firmware canenable or implement aspects described herein, including disclosedmethod(s). The term “article of manufacture” as used herein is intendedto encompass a computer program accessible from any computer-readabledevice, carrier, or media. For example, computer readable media caninclude but are not limited to magnetic storage devices (e.g., harddisk, floppy disk, magnetic strips . . . ), optical discs (e.g., compactdisc (CD), digital versatile disc (DVD), blu-ray disc (BD) . . . ),smart cards, and flash memory devices (e.g., card, stick, key drive . .. ).

Computing devices typically include a variety of media, which caninclude computer-readable storage media or communications media, whichtwo terms are used herein differently from one another as follows.

Computer-readable storage media can be any available storage media thatcan be accessed by the computer and includes both volatile andnonvolatile media, removable and non-removable media. By way of example,and not limitation, computer-readable storage media can be implementedin connection with any method or technology for storage of informationsuch as computer-readable instructions, program modules, structureddata, or unstructured data. Computer-readable storage media can include,but are not limited to, RAM, ROM, EEPROM, flash memory or other memorytechnology, CD-ROM, digital versatile disk (DVD) or other optical diskstorage, magnetic cassettes, magnetic tape, magnetic disk storage orother magnetic storage devices, or other tangible and/or non-transitorymedia which can be used to store desired information. Computer-readablestorage media can be accessed by one or more local or remote computingdevices, e.g., through access requests, queries or other data retrievalprotocols, for a variety of operations with respect to the informationstored by the medium.

Communications media typically embody computer-readable instructions,data structures, program modules or other structured or unstructureddata in a data signal such as a modulated data signal, e.g., a carrierwave or other transport mechanism, and includes any information deliveryor transport media. The term “modulated data signal” or signals refersto a signal that has one or more of its characteristics set or changedin such a manner as to encode information in one or more signals. By wayof example, and not limitation, communication media include wired media,such as a wired network or direct-wired connection, and wireless mediasuch as acoustic, RF, infrared and other wireless media.

What has been described above includes examples of systems and methodsthat provide advantages of the one or more aspects. It is, of course,not possible to describe every conceivable combination of components ormethods for purposes of describing the aspects, but one of ordinaryskill in the art may recognize that many further combinations andpermutations of the claimed subject matter are possible. Furthermore, tothe extent that the terms “includes,” “has,” “possesses,” and the likeare used in the detailed description, claims, appendices and drawingssuch terms are intended to be inclusive in a manner similar to the term“comprising” as “comprising” is interpreted when employed as atransitional word in a claim.

As used in this application, the terms “component,” “system,” and thelike are intended to refer to a computer-related entity or an entityrelated to an operational apparatus with one or more specificfunctionalities, wherein the entity can be either hardware, acombination of hardware and software, software, or software inexecution. As an example, a component may be, but is not limited tobeing, a process running on a processor, a processor, an object, anexecutable, a thread of execution, computer-executable instructions, aprogram, and/or a computer. By way of illustration, both an applicationrunning on a server or network controller, and the server or networkcontroller can be a component. One or more components may reside withina process and/or thread of execution and a component may be localized onone computer and/or distributed between two or more computers. Also,these components can execute from various computer readable media havingvarious data structures stored thereon. The components may communicatevia local and/or remote processes such as in accordance with a signalhaving one or more data packets (e.g., data from one componentinteracting with another component in a local system, distributedsystem, and/or across a network such as the Internet with other systemsvia the signal). As another example, a component can be an apparatuswith specific functionality provided by mechanical parts operated byelectric or electronic circuitry, which is operated by a software, orfirmware application executed by a processor, wherein the processor canbe internal or external to the apparatus and executes at least a part ofthe software or firmware application. As yet another example, acomponent can be an apparatus that provides specific functionalitythrough electronic components without mechanical parts, the electroniccomponents can include a processor therein to execute software orfirmware that confers at least in part the functionality of theelectronic components. As further yet another example, interface(s) caninclude input/output (I/O) components as well as associated processor,application, or Application Programming Interface (API) components.

The term “set”, “subset”, or the like as employed herein excludes theempty set (e.g., the set with no elements therein). Thus, a “set”,“subset”, or the like includes one or more elements or periods, forexample. As an illustration, a set of periods includes one or moreperiods; a set of transmissions includes one or more transmissions; aset of resources includes one or more resources; a set of messagesincludes one or more messages, and so forth.

In addition, the term “or” is intended to mean an inclusive “or” ratherthan an exclusive “or.” That is, unless specified otherwise, or clearfrom context, “X employs A or B” is intended to mean any of the naturalinclusive permutations. That is, if X employs A; X employs B; or Xemploys both A and B, then “X employs A or B” is satisfied under any ofthe foregoing instances. Moreover, articles “a” and “an” as used in thesubject specification and annexed drawings should generally be construedto mean “one or more” unless specified otherwise or clear from contextto be directed to a singular form.

What is claimed is:
 1. A system, comprising: at least one memory thatstores computer-executable instructions; and at least one processor,communicatively coupled to the at least one memory, that facilitatesexecution of the computer-executable instructions to at least: identifya segment of a wireless communications network for assignment ofscrambling codes to a plurality of base stations located within thesegment; determine a core of the segment, wherein the core is a portionof the segment comprising at least a pre-defined number of basestations; reserve a first set of scrambling codes of the scramblingcodes for a first set of base stations of the plurality of base stationswithin the core; define a center for the segment; assign a second set ofscrambling codes of the scrambling codes to a second set of basestations of the plurality of base stations in the segment, wherein theassignment is performed in an order based on distances of the second setof base stations from the center, and wherein a first base station inthe first set of base stations and a second base station of the secondset of base stations are assigned a same scrambling code; and convey thefirst set of scrambling codes and the second set of scrambling codes tothe first set of base stations and the second set of base stations,respectively.
 2. The system of claim 1, wherein the at least oneprocessor further facilitates the execution of the computer-executableinstructions to identify at least one primary scrambling code thatsatisfies a condition with respect to a distance parameter for each basestation of the second set of base stations being evaluated.
 3. Thesystem of claim 2, wherein the at least one processor furtherfacilitates the execution of the computer-executable instructions todecrease a length of the distance parameter in response to at least onebase station from the second set of base stations failing to satisfy thecondition with respect to the distance parameter.
 4. The system of claim1, wherein the at least one processor further facilitates the executionof the computer-executable instructions to identify at least one primaryscrambling code of the scrambling codes that satisfies a condition withrespect to a distance parameter and a coverage range for the first basestation and the second base station.
 5. The system of claim 1, whereinthe at least one processor further facilitates the execution of thecomputer-executable instructions to reconfigure at least a portion ofthe scrambling code assignment in response to a determination that atleast two base stations defined as neighbors share a common primaryscrambling code.
 6. The system of claim 1, wherein the at least oneprocessor further facilitates the execution of the computer-executableinstructions to reconfigure at least a portion of the scrambling codeassignment in response to a determination that at least two basestations share a common primary scrambling code and are defined asneighbors of a third cell.
 7. The system of claim 1, wherein the atleast one processor further facilitates the execution of thecomputer-executable instructions to apply a restriction to a third setof scrambling codes assigned to a third set of base stations locatedoutside a boundary of the segment of the wireless communicationsnetwork.
 8. The system of claim 7, wherein the at least one processorfurther facilitates the execution of the computer-executableinstructions to bypass the assignment based on a distance between thethird set of base stations and the second set of base stations.
 9. Thesystem of claim 1, wherein the at least one processor furtherfacilitates the execution of the computer-executable instructions toassign base stations of the plurality of base stations on a same cellscrambling codes that conform to at most a pre-defined separationamount.
 10. A method, comprising: determining, by a system comprising aprocessor, a first allocation of a first set of primary scrambling codesto a first set of base stations of a plurality of base stations locatedin a populated area of a wireless communications network having at leasta pre-defined population; determining, by the system, a secondallocation of a second set of primary scrambling codes for each basestation of a second set of base stations of the plurality of basestations, wherein the determining is based on at least one of a distancebetween base stations of the plurality of base stations and a coveragearea of each base station; and assigning by the system, the first set ofprimary scrambling codes to the first set of base stations and thesecond set of primary scrambling codes to the second set of basestations, wherein scrambling codes of the first set of primaryscrambling codes are reused in the second set of primary scramblingcodes.
 11. The method of claim 10, wherein the determining the secondallocation comprises: evaluating, by the system, the distance between afirst base station of the first set of base stations and a second basestation of the second set of base stations; determining, by the system,the distance is greater than a predefined distance; and reserving aprimary scrambling code assigned to the first base station for reuse bythe second base station.
 12. The method of claim 10, wherein thedetermining the second allocation comprises: determining, by the system,the distance between the first base station of the first set of basestations and a second base station of the second set of base stations;determining, by the system, that the distance is less than a predefineddistance; evaluating, by the system, a second distance between a thirdbase station of the first set of base stations and the second basestation; determining, by the system, the second distance is greater thanthe predefined distance; and reserving a primary scrambling code of thethird base station for reuse by the second base station.
 13. The methodof claim 10, wherein the determining comprises: measuring, by thesystem, a plurality of distances between first base stations of thefirst set of base stations and second base stations of the second set ofbase stations; determining, by the system, that at least one distance ofthe plurality of distances does not satisfy a condition with respect toa predefined distance; reducing a length of the predefined distance;re-measuring, by the system, the plurality of distances between basestations of the first set of base stations and base stations of thesecond set of base stations; and determining, by the system, at leastone distance of the plurality of distances satisfies the condition withrespect to the predefined distance.
 14. The method of claim 10, furthercomprising: identifying, by the system, that the first base station anda second base station are defined as neighbors share a same primaryscrambling code; and changing, by the system, the primary scramblingcode of the first base station or the second base station.
 15. Themethod of claim 10, further comprising: identifying, by the system, thatthe first base station and a second base station are defined asneighbors by a third base station, wherein the first base station andthe second base station are assigned a same primary scrambling code; andchanging, by the system, the primary scrambling code of the first basestation or the second base station as a result of the identifying. 16.The method of claim 10, further comprising assigning base stations ofthe plurality of base stations on a same cell scrambling codes thatconform to at most a pre-defined separation amount, wherein the basestations are located in geographic regions, wherein a geographic regionis a cell.
 17. A non-transitory computer-readable storage medium storingcomputer-executable instructions that, in response to execution, cause asystem including a processor to perform operations, comprising:identifying a portion of a network that comprises at least a pre-definednumber of base stations; assigning primary scrambling codes to a firstset of base stations in the portion of the network; evaluating a secondset of base stations in the portion of the network for reuse of theprimary scrambling codes, wherein the evaluating is based on a distancebetween base stations that are assigned a same scrambling code and acoverage area of each base station; and selectively applying the primaryscrambling codes to the second set of base stations as a result of theevaluating, wherein a same primary scrambling code is applied to a firstbase station in the first set of base stations and a second base stationin the second set of base stations.
 18. The non-transitorycomputer-readable storage medium of claim 17, wherein the operationsfurther comprise: identifying at least one primary scrambling code basedon a distance parameter for each base station in the second set of basestations being evaluated for scrambling code reuse.
 19. Thenon-transitory computer-readable storage medium of claim 17, wherein theoperations further comprise: reassigning a primary scrambling code ofthe second base station in response to the second base station and thefirst base station being neighbors or in response to a third basestation identifying the second base station and the first base stationas neighbors.
 20. The non-transitory computer-readable storage medium ofclaim 17, wherein the operations further comprise: bypass processing ofscrambling codes associated with a third set of base stations, whereinthe third set of base stations are located outside the portion of thenetwork.